Advances in technology are driving both an evolution of our approach to the prevention of HIV and the care of those living with HIV, and of the means we use to disseminate prevention and treatment approaches. New technologies, including mobile apps and web-based prevention services, have been proposed as one solution to help bring HIV testing, pre-exposure prophylaxis (PrEP) screening, PrEP adherence, and antiretroviral adherence to scale. To support a program of research in these areas, core services, resources, and technical capacities are needed. Co-directed by Sullivan and Hightow-Weidman, the Technology Core will provide services for technology- related fields, including mobile technologies, web-based platforms, laboratory platforms, online recruitment and technology-related ethics issues to support the overall iTech strategy. The Core is conceptualized as a service center, to which individual investigators from within the iTech or the broader ATN community of funded U19s can request specialized assistance or request to use shared resources (e.g., video counseling platform, image libraries for advertising). Quality control of core services will be assessed by review of the tangible results of service requests (e.g., requirements documents, summaries of app testing, technical documents, laboratory protocols) by the Core co-directors. Centralization of resources will allow development of deep expertise, minimize redundant costs of common tools, and facilitate connections across research projects and sites. The specific aims of the Technology Core are to: 1) Provide technology-support to all six research projects in the iTech and promote the development of sustainable technologies for addressing the HIV care continuum among youth; 2) To be a resource to other funded U19s by providing technical assistance and support on all technology-related aspects of recruitment, retention, implementation and evaluation; 3) Develop and disseminate best practices for the execution and evaluation of technology-based interventions within the Adolescent Trials Network and stay up to date with technological advances, including those related to platform/system changes, new technologies (e.g. wearables, sensors, point of care testing) and improved methodologies (e.g. EMA, virtual reality); and 4) Develop and maintain standards for the ethical conduct of online/technology-based interventions for youth through ongoing consultation with community advisors. In addition to supporting the iTech research and pilots studies, the Technology Core will work collaboratively with the Management Core to ensure project and subject recruitment venue (SRV) milestones are met, data standards are upheld and dissemination is timely. Collaboration with the Analytic Core will serve to ensure the development, execution, analysis, and dissemination phases of each research project succeed. The Technology Core will also serve as a resource to other funded U19s providing technical assistance on mobile technologies, web-based platforms, home specimen collection, and online recruitment, retention and participant management.